Can You Buy Penicillin Online?

By Zina Semenovskaya, MD
Medically reviewed checkmarkMedically reviewed
December 4, 2021

More than 75 years since its chance discovery in a London laboratory, penicillin is still widely used to treat infections and save lives around the world every day.

But using the medication too often or for the wrong conditions can cause it to become ineffective.

In order to ensure quality of care, penicillin requires a prescription from a healthcare provider. 

While penicillin does require a prescription, thanks to telemedicine, that doesn’t mean that it requires an in-person visit.

Knowing when and how to connect with a healthcare provider online can help you to get a prescription for penicillin when needed.

In this article, I’ll explain what penicillin is, how you can buy it online, and its uses, side effects, and dosage.

I’ll also outline some risks and warnings about taking penicillin, and tell you when you should speak with a doctor.

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What is Penicillin?

Penicillin is a narrow-spectrum antibiotic that is effective against gram-positive bacteria, including:

  • Streptococcus pneumoniae
  • Groups A, B, C, and G streptococci
  • Nonenterococcal group D streptococci
  • Virdians group streptococci
  • Non-penicillinase producing staphylococcus

Can I Buy Penicillin Online?

Purchasing penicillin requires a prescription from a licensed healthcare provider, but that doesn’t mean you have to visit them in person.

Many online resources connect you with providers over phone, video, or text so that you can discuss your symptoms and explore treatment options, including antibiotics like penicillin.

Getting a prescription online

Using a trusted and professional resource, getting a prescription online, when appropriate, is simple.

With K Health, simply download the app to check your symptoms, explore conditions and treatments, and if needed, text with a doctor in minutes.

Other platforms may work similarly. 

Just be sure that you are connected with a board-certified medical professional.

Can I buy penicillin over-the-counter (OTC)?

Not in the United States.

In the U.S., oral, intravenous (IV), and intramuscular (IM) antibiotics, including penicillin, are only available via prescription, so you need to speak to a medical professional to obtain them.

Your provider will ask about your symptoms and medical history, and may run additional tests to determine which antibiotic, if any, is right for you.

Though penicillin isn’t available without a prescription, some topical antibiotic creams and ointments can be purchased over-the-counter (OTC).

These can be used to treat minor cuts, scrapes, and burns.

These OTC antibiotic topical creams include:

  • Bacitracin (Neosporin)
  • Polymyxin (Polysporin)
  • Neomycin (Neosporin Plus Pain Relief)
  • Benzoyl peroxide (Proactiv)

Penicillin Uses

Penicillin is an antibiotic drug used to treat infections caused by bacteria, including:

  • Pneumonia and other respiratory infections
  • Scarlet fever
  • Ear, skin, gum, mouth, and throat infections
  • Syphilis

Like other antibiotics, penicillin will not treat a cold, flu, or other viral infections.

Penicillin Side Effects

The most common, and often mild, side effects include:

If any of these symptoms gets worse or won’t go away, reach out to a healthcare professional.

Having these side effects doesn’t mean that you have an allergy to penicillin.

If you do have side effects, always let your healthcare provider know when you’re being prescribed antibiotics in the future. 

Penicillin Dosage

The exact dosage and timing of penicillin medications will vary depending on what condition you are treating.

For infections, penicillin is generally taken every 6 hours (four times a day) or every 8 hours (three times a day) until the course is completed.

For the treatment of rheumatic fever, penicillin is generally taken twice a day. 

In most cases, it’s a good idea to take penicillin at about the same time each day.

How should I take penicillin?

As with any new medication, it’s important to follow the directions on the prescription label carefully.

If any of the directions are unclear, ask your provider or pharmacist about how to proceed.

Penicillin is often taken as a tablet or as an oral solution.

It’s important to store the medication at room temperature and away from excess heat and moisture.

Sometimes penicillin is administered as an injection, and this should be done by a licensed healthcare provider.

Missed dose

Take your missed dose as soon as you remember, unless it’s almost time for the next one.

In that case, skip the missed dose and continue the regular dosing schedule.

Never take a double dose to make up for a missed one.

Antibiotic resistance

The overprescription and improper use of antibiotics worldwide has led to some bacteria learning how to survive against the most powerful antibiotics designed to kill them off.

This is called antibiotic resistance, and it’s a growing public health issue across the world.

This is partly why antibiotics are only available with a prescription.

Every year, antibiotic-resistant bacteria infect more than two million people in the U.S., often leading to hospitalizations or, in some cases, death. 

To fight antibiotic resistance, the CDC designated better-informed use and prescription of antibiotics as a national priority.

You can do your part by taking antibiotics as prescribed, not sharing your antibiotics with anyone or saving them, and never pressuring a healthcare provider to prescribe antibiotics.

Penicillin Risks and Warnings

Before taking penicillin, tell your provider about any medications, vitamins, supplements, or herbal products you’re currently taking and whether or not you’re pregnant or breastfeeding.

It’s also important to disclose whether or not you’re allergic to penicillin or any other antibiotics.

If you do have an allergy, it’s helpful if you know what your reaction was, because some symptoms, such as nausea, are not a true allergy.

Tell your provider about any chronic health conditions you have, including kidney disease, asthma, hay fever, or other allergies.

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When to See a Doctor

Reach out to your provider immediately if you experience any of the possible severe side effects of penicillin, including:

  • Rash
  • Hives
  • Itching
  • Hoarseness
  • Wheezing
  • Difficulty swallowing or breathing
  • Joint pain
  • Swelling of the throat, tongue or lips
  • A return of any of the symptoms of your original infection (including fever, sore throat, chills, etc.)
  • Severe diarrhea

How K Health Can Help 

Did you know you can get affordable primary care with the K Health app?

Download K to check your symptoms, explore conditions and treatments, and if needed text with a doctor in minutes. K Health’s AI-powered app is HIPAA compliant and based on 20 years of clinical data.

Frequently Asked Questions

Can you buy over-the-counter (OTC) penicillin?
No. Penicillin requires a prescription from a medical professional. Some topical antibiotics used to treat minor cuts, scrapes, and burns are available over the counter.
What is a good substitute for penicillin?
Macrolides are a common alternative for people who are allergic to penicillin. They can be used to treat some types of pneumonia, STIs, and other infections.
Can you give yourself penicillin?
Penicillin requires a prescription, but that doesn’t mean you need to see a provider in person. You can speak with a provider on the phone or online to get the right prescription. But be sure to speak with them about how long to take your medication and always follow the instructions on the label or packaging.
Is penicillin available in the market?
To buy penicillin, you’ll need a prescription from a healthcare provider. Selling penicillin online without a prescription is illegal in the US. It also puts customers at risk of using poor quality medication and receiving poor quality of care.

K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.

Zina Semenovskaya, MD

Dr. Semenovskaya specializes in emergency medicine, and received her medical degree from Weill Cornell Medical College. She is currently the medical director at Remote Emergency Medicine Consulting, LLC and splits her time working clinically as an emergency medicine attending in California and Alaska. She is the first of our doctors to be fluent in Russian.